Signs of a Bad Ficm on a Duramax

A Duramax engine is a great option for anyone in the market for a powerful and efficient diesel engine. However, like any engine, the Duramax can have its share of problems. One potential issue is a bad Fuel Injection Control Module (FICM).

There are several symptoms that can indicate a problem with the FICM, and it’s important to be aware of them so you can get your engine serviced before serious damage is done.

If you’re the owner of a Duramax diesel truck, then you know that a bad FICM can lead to all sorts of problems. But what are the signs of a bad FICM? Here are four telltale signs:

1. Your truck is hard to start. If your truck takes longer than usual to start up, or if it’s difficult to get it started at all, then that’s a sign that your FICM may be going bad. 2. Your truck isn’t running as smoothly as it used to.

If you notice that your engine is missing, hesitating, or stalling, then those are all signs that something is wrong with your FICM. 3. You’re getting less power and mileage than usual. A failing FICM can lead to reduced power and fuel efficiency, so if you notice either of those things happening with your truck, it’s time to have your FICM checked out.

4. Your check engine light is on. This one is pretty self-explanatory – if your check engine light is on, there’s definitely something wrong under the hood! And in this case, it’s likely due to a failing FICM.

If you notice any of these signs with your Duramax diesel truck, then it’s time for a trip to the mechanic – specifically, someone who specializes in Duramax trucks! Don’t let a failing FICM ruin your day (or week… or month). Get it fixed sooner rather than later and enjoy driving your Duramax again!

Signs of a Bad Ficm on a Duramax


How Do You Test a Ficm on a Duramax?

To test a Ficm on a Duramax, you’ll need to connect a voltmeter to the positive and negative terminals of the Ficm. With the engine off, you should see a reading of around 12.6 volts. If the reading is significantly lower than that, it indicates that the Ficm is not working properly and needs to be replaced.

How Do I Know If My Ficm is Bad?

Your FICM is the Fuel Injection Control Module, and it’s responsible for providing power to the injectors. If your FICM is failing, you’ll likely see one or more of the following symptoms: 1. Engine misfires – This can be caused by a loss of power from the FICM to the injectors.

As a result, the air/fuel mixture in the cylinders isn’t being burned properly, leading to engine misfires. 2. Rough idle – A failing FICM can cause your engine to run rough at idle. This is because the injectors aren’t receiving enough power to provide a smooth flow of fuel into the cylinders.

3. Poor fuel economy – A failing FICM can also lead to poor fuel economy as the injectors aren’t able to deliver an optimal amount of fuel into the cylinders. This results in wasted fuel and reduced performance from your engine. 4. Check Engine Light (CEL) – The CEL may come on if your FICM is failing as it’s detecting an issue with how much power is being supplied to the injectors.

5 Diagnostic Trouble Codes (DTCs) – If your car has a OBD-II port, you can plug in a code reader and check for any diagnostic trouble codes (DTCs).

How Do You Know If Your Ecm is Bad on a Duramax?

If your ECM is bad on a Duramax, you’ll likely see one or more of the following symptoms: 1. The engine won’t start. This is probably the most common symptom of a bad ECM.

If the engine won’t start, it’s likely because the ECM isn’t sending the correct signal to the fuel injectors. 2. The engine runs erratically. If the ECM is failing, it can cause the engine to run rough or stall unexpectedly.

You may also see a decrease in power and an increase in fuel consumption. 3. Check Engine Light is on. A faulty ECM will often trigger the Check Engine Light (CEL).

If you see the CEL, it’s worth taking your truck to a mechanic for diagnosis. 4. The truck isn’t responding to throttle input correctly. This can be another symptom of a failing ECM – if it’s not sending the correct signals to the throttle body, then the truck may not accelerate properly when you hit the gas pedal.

What is Ficm on Duramax?

The FICM on Duramax is the Fuel Injection Control Module. It is responsible for controlling the fuel injectors in your engine. The module is located on the top of the engine, behind the throttle body.

It is a black box that has two wires going to it. One wire goes to the battery and the other goes to the ground. The FICM can fail due to a number of reasons.

The most common cause of failure is water damage. This can happen if your truck gets flooded or if you drive through a puddle that is deeper than usual. Water can enter the FICM through cracks in the housing or through loose wiring connections.

If water enters the module, it can short out the circuitry and cause permanent damage. Other causes of FICM failure include physical damage, corrosion, and electrical problems. Physical damage can occur if something hits the module while it’s installed in your engine bay.

Corrosion can occur if moisture gets inside of the module and causes rusting or other types of deterioration. Electrical problems can stem from faulty wiring or from a power surge that damages sensitive components inside of the unit. FICM failures are typically not covered by warranty, so it’s important to be aware of potential issues and have a plan in place in case yours does fail unexpectedly.

$1.00 Capacitor Blew Up My Duramax FICM! LLY Duramax FICM Short Circuit Diagnosis & Replacement.

Lb7 Lost Communication With Ficm

If you have a 2001-2004 GMC or Chevrolet with a Duramax Diesel and your truck has developed a “lost communication with FICM” error, there are some things you can do to troubleshoot the problem. The first thing to check is all of the fuses related to the FICM. These are located in the fuse box under the hood on the driver’s side.

If any of these fuses are blown, they will need to be replaced before proceeding. Next, check all of the connections at the FICM itself. Make sure that none of the wires are loose or damaged.

If everything looks good here, move on to checking the voltage at the battery terminals. The voltage should be between 13 and 14 volts when measured with a voltmeter. If both of those things check out, it’s likely that your problem is with the actual FICM itself.

This is a fairly common issue with these trucks and unfortunately, there isn’t really a great fix for it other than replacing the entire unit. Thankfully, there are plenty of aftermarket options available that will work just as well as (if not better than) the OEM unit.

2005 Duramax Bad Ficm

If you’re a fan of diesel trucks, then you’re probably familiar with the 2005 Duramax. This truck was equipped with a 6.6-liter turbocharged V8 engine that could produce up to 360 horsepower and 650 lb-ft of torque. While this truck was certainly powerful, it was also known for having some issues with its fuel injection system.

One of the most common problems that owners of this truck experience is called “bad FICM.” This stands for fuel injector control module, and it’s responsible for regulating the flow of fuel to the injectors. When this component fails, it can cause all sorts of problems, including poor engine performance, rough idling, and increased fuel consumption.

Fortunately, there are plenty of aftermarket options available to fix this problem. You can find replacement modules that will work just as well as the original one (or better). You can also install an upgraded module that includes additional features and improved reliability.

Whichever route you choose, be sure to do your research so you can find a product that will fit your needs and budget.

Lly Duramax Ficm

The Lly Duramax Ficm is a high performance fuel injection control module that is designed for use with Duramax engines. This module is capable of controlling the injectors on up to eight cylinders, and it features a built-in diagnostic system that can be used to troubleshoot any issues that may arise. The Lly Duramax Ficm also includes a number of safety features, such as an overheat protection circuit and a low voltage cutoff, that help to ensure that your engine will always run smoothly and efficiently.

How Do I Test My Ficm Duramax

If you have a Duramax diesel engine, you may be wondering how to test your FICM. The FICM, or fuel injection control module, is responsible for delivering the correct amount of fuel to the injectors at the right time. If it isn’t working properly, your engine will run poorly and may eventually fail.

There are a few different ways that you can test your FICM. One way is to use a multimeter to check the voltage output of the module. This should be done when the engine is running and under load (such as when driving up a hill).

The voltage should be between 47 and 53 volts. If it’s outside of this range, it’s likely that your FICM is faulty. Another way to test your FICM is with an oscilloscope.

This will allow you to see the waveform of the voltage output from the module. It should be a smooth, sinusoidal waveform if everything is working properly. If there are any spikes or irregularities in the waveform, this indicates that there is a problem with the FICM.

If you suspect that your FICM is not working properly, it’s important to get it checked out by a qualified mechanic as soon as possible.


If your Duramax is experiencing any of the following issues, it may be time to replace the FICM: -Hard starts -Extended cranking times

-Intermittent starting issues -Stalling or hesitating under load

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